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Smallest prime p such that both p +/- 2n are primes closest to p, or zero if no such prime exists.
1

%I #12 Oct 27 2017 09:13:04

%S 5,0,53,0,0,211,0,0,20201,0,0,16787,0,0,69623,0,0,255803,0,0,247141,0,

%T 0,3565979,0,0,6314447,0,0,4911311,0,0,12012743,0,0,23346809,0,0,

%U 43607429,0,0,34346287,0,0,36598607,0,0,51042053,0,0,460475569,0,0

%N Smallest prime p such that both p +/- 2n are primes closest to p, or zero if no such prime exists.

%C Such triples of primes occur only for n divisible by 3 (except for the first term with n=1).

%F p-2n, p and p+2n are three successive primes and p is the least such prime.

%e a(36)=23346809 because 23346809-72, 23346809 and 23346809+72 are three successive primes and 23346809 is the least such prime.

%Y Cf. A054342, A102723, A023186.

%K nonn

%O 1,1

%A _Zak Seidov_, Feb 12 2005

%E More terms from _Robert G. Wilson v_, Feb 22 2005

%E Definition, Formula, and Example clarified by _Jonathan Sondow_, Oct 27 2017